If you love to chat in group like in Yahoo! Messenger Conference, maybe you also like to use Group Chat in Gmail. Group Chat is new feature enabled in Gmail which you can chat with your buddies online. You can invite all your friends in Group Chat because the numbers of person can join the Group Chat are Unlimited.
To start a Group Chat, first chat with one of your friend, then click on Options and choose Group Chat. From there, you can invite other buddies to join in the group. The discussion will continue even you are logout from the group discussion. If you have logout and want to rejoin the group, you need to get invited by somebody who is currently in the Group Chat.